Emergent complications of assisted reproduction: expecting the unexpected.

With the increasing popularity of assisted reproductive technology (ART), radiologists are more likely to encounter associated complications, especially in an emergency setting. These complications include ovarian hyperstimulation syndrome (OHSS), ovarian torsion, and ectopic and heterotopic pregnancy. OHSS occurs following ovulation induction or ovarian stimulation and manifests with bilateral ovarian enlargement by multiple cysts, third-spacing of fluids, and clinical findings ranging from gastrointestinal discomfort to life-threatening renal failure and coagulopathy. Enlarged hyperstimulated ovaries are at risk for torsion. Clinical symptoms are often nonspecific, and ovarian torsion should be suspected and excluded in any female patient undergoing infertility treatment who presents with severe abdominal pain. The most consistent imaging finding is asymmetric enlargement of the twisted ovary. There is also an increased risk for ectopic pregnancy following ART, with a relative increased risk for rarer and more lethal forms, including interstitial and cervical ectopic pregnancies. Heterotopic pregnancy refers to simultaneous intrauterine and ectopic pregnancies and has an incidence of 1%-3% in ART patients. Careful evaluation of the adnexa is critical in this patient population, even when an intrauterine pregnancy has been confirmed. Ultrasonography is the first-line imaging modality for the evaluation of complications of ART, although nonspecific symptoms may sometimes lead to cross-sectional imaging being performed. Familiarity with the multimodality imaging appearance of these entities will allow accurate and timely diagnosis and help avert potentially fatal consequences.

Comparing the diagnostic performance of MRI versus CT in the evaluation of acute nontraumatic abdominal pain during pregnancy.

The objectives of this study were to document the utilization of MRI compared with CT in pregnant patients presenting with acute nontraumatic abdominal pain at our institution and to compare the diagnostic performance of the two modalities. A retrospective review identified all pregnant patients at our institution who had MRI or CT exams of the abdomen and/or pelvis for acute nontraumatic abdominal pain over a 3-year period from January 2008 through December 2010. The imaging diagnoses were compared with pathologic data or operative findings as the primary reference standard or with clinical follow-up and laboratory data as the secondary reference standard. Patients without surgically proven diagnoses were followed clinically until delivery, when possible. Ninety-four pregnant patients were included in this study: 61 MRI exams were performed in 57 patients, 44 CT exams were performed in 43 patients (including six patients who had both), and 72 patients (77 %) had ultrasound prior to cross-sectional imaging, with the appendix specifically assessed in 25 patients but visualized in only two of them. Of 61 MRI exams, 24 were considered positive for imaging diagnoses, 33 were negative, and 4 were equivocal. Of 44 CT exams, 24 were positive and 20 were negative. The test characteristics for MRI and CT in the diagnosis of acute abdominal pain were as follows: sensitivity 91 and 88 %, specificity 85 and 90 %, positive predictive value 81 and 91 %, negative predictive value 94 and 8 5 %, and diagnostic accuracy 88 and 88 %, respectively. Differences were not statistically significant (p value = 1). The majority of MRIs (34/61 = 56 %) were read by emergency radiologists. MRI and CT performed equally well in the evaluation of acute nontraumatic abdominal pain during pregnancy. Given its lack of ionizing radiation, MRI may be preferable. Given that the majority of MRIs were read by radiologists specializing in emergency imaging, this is a technique that emergency radiologists should be comfortable interpreting.

Radiologic-pathologic correlation in acute appendicitis: can we use it as a quality measure to assess interpretive accuracy of radiologists?

Radiologic-pathologic correlation was evaluated as a quality assurance tool by documenting error rates of 18 radiologists interpreting computed tomographic (CT) scans for acute appendicitis in 763 patients. The departmental error rate was 3.1%. Meaningful individual error rates could be determined in only the seven radiologists who interpreted ≥30 CT scans for acute appendicitis. Radiologic-pathologic correlation is an effective departmental monitor of interpretive accuracy, but individual accuracy can be assessed only for radiologists reading a large number of cases with pathologic proof.